The linear polarization of x rays can be measured by the modulation of the azimuth distribution of scattered photons as derived from the coincident scintillations of a pair of wire- like detectors in a tight package of many. We computed the response of such an experiment by simulations with the MCNP code. We discuss the improvement of the sensitivity, in particular at lower energies, by the use of a combination of fibers of two different scintillators. Possibilities offered by the new scintillating material YAP are also discussed.